The increased availability of food with extended shelf lives has established an expectation for food industry manufacturers to determine accurate shelf-life data. Regulatory agencies, retail partners and consumers expect to see accurate product use by and best before dates to ensure consumer safety. To provide accurate shelf-life determinations, food manufacturers need reputable testing methods and data to analyze the various physical, microbiological and chemical properties of their products and packaging. This is accomplished primarily through food shelf life studies and testing.
What Is Food Shelf Life Testing?
Shelf life is generally defined as how long a food product will retain quality during storage, with shelf life officially starting when the food is manufactured. Food shelf-life testing covers several types of tests conducted to show how food products change as they age. These tests use various methods, including chemical, analytical, sensory and microbiological testing, and apply them to different shelf life-affecting factors, including the product’s formula, processing, size, packaging and storage conditions.
Each set of tests for a specific product is called a shelf life study, and a new study needs to be conducted for each product and any new iterations that involve a change in any product qualities. Combined, the data produced can help manufacturers set use by, sell by, best by and expiration dates.
How to Determine the Shelf Life of a Food Product
The shelf life of a food product depends on several physical, microbiological and chemical processes along with contributing factors like processing, packaging and storage conditions. Determining shelf life involves looking at each of these factors and how they affect product deterioration in a shelf-life study. These studies typically involve the following steps:
- Identify spoilage causes: Each product is unique, with a set of characteristics that may contribute to spoilage differently. Test specialists analyze the subject of the study and identify methods by which it may deteriorate over time.
- Select test: After identifying potential points of spoilage, test designers identify the best testing options for the product. These can include sensory evaluation, chemical and physical analysis and microbiological shelf-life testing.
- Plan study: Study designers plan out the shelf life study, including the length and date of the study, what tests to conduct and when, and how many samples will be collected at each sampling date.
- Conduct study: After confirming the plan with the manufacturer, the study designers conduct the shelf-life tests. They may also conduct follow-up studies if results significantly vary.
- Determine shelf life: At the conclusion of the study, testers organize and analyze the data to create a complete picture of the product’s decay rate. Using this data, the testers and manufacturers determine a reasonable shelf life for the product.
- Monitor shelf life: Once the product is on the market, manufacturers regularly test samples of products at various points and ages in the distribution system to ensure that the shelf life is appropriate.
The exact details of these shelf life study steps differ depending on the product and the methods used. For example, designers may choose accelerated shelf-life studies that purposefully increase the rate of product deterioration, predictive modeling to model bacterial growth or challenge tests to monitor the growth of cold-tolerant pathogens.
Important Components of Food Shelf Life Testing
Designing a shelf life study of food products requires tailoring the tests to each product’s unique features. This customization ensures that the shelf life data is accurate to provide information for an appropriate determination. To determine the right tests, test designers consider several factors before planning the study, including the following:
- Microbiology: The microbiology of the product is one of the most critical aspects to consider during study design. This component involves determining whether the product supports microbiological activity like mold, bacteria and pathogens and how this growth may affect product spoilage or consumer safety.
- Water activity and pH: Water activity and the pH of the product relate to the microbiology component, as changes in water activity and pH may change the product’s susceptibility to microbiological growth.
- Rancidity: Rancidity is the result of oxidation of fats and oils in a food product. It compromises the nutritional value, scent and taste of a product. Lipid oxidation tests measure rancidity throughout the test cycle, and the type of lipid test needed varies depending on the moisture and fat levels in the product.
- Unstable compounds: Some compounds, including vitamins and nutraceutical active ingredients, are unstable and may degrade over time. Certain tests can determine the rate of loss for these compounds.
- Olfactory changes: Taste and smell are significant factors for consumers and should be included in the testing process. Testers regularly smell and taste samples to determine the rate of deterioration in each area.
- Moisture levels: Moisture levels of a product may change depending on the packaging and affect the food’s quality over time. Moisture analyses are quick, inexpensive and relatively non-destructive to run, so these are often conducted throughout a food shelf life study.
- Color changes: Color changes are another factor that consumers notice often pay attention to and are usually included a shelf life studies through visual inspection and photography.
Studies may include any number of these test types depending on the product, the manufacturer and applicable regulatory entities. Each test is conducted at specific intervals to monitor the rate of degradation, and each component is analyzed individually and in combination with others to determine the appropriate shelf life.
Are Food Shelf Life Studies Mandatory?
It’s essential to note that federal regulations do not mandate product dating for any food product except for infant formula. According to the U.S. Department of Agriculture (USDA), date labeling on foods is voluntary, but if the manufacturer elects to add it, it must be truthful and not misleading. For specific types of food, voluntary date labeling must also comply with specific regulations. For example, shelf life dates on meat, poultry and egg products must comply with Food Safety and Inspection Service (FSIS) regulations.
Despite the lack of federal regulation, most food retailers require their food manufacturer partners to display some type of shelf life labels on their products for inventory management purposes. Additionally, many consumers expect date labels on their foods to help them make purchasing decisions and evaluate the safety of the food in their homes.
Our Food Shelf Life Testing Abilities
If you need shelf life analysis of food products, Log 10 provides high-quality testing services to support your product development needs. Our technical team of microbiology and food science experts provides a range of testing services in our food shelf life testing lab, including:
- Rancidity testing: Log 10 offers several lipid testing options to run accurate rancidity testing on any food product.
- Accelerated shelf life studies: Accelerated shelf life studies increase the deterioration rates of products and use those results to extrapolate shelf life estimates.
- Food chemistry testing: Log 10 conducts several food chemistry tests to verify the contents of food products, including food moisture, pH and water activity testing.
- Stability testing in various storage conditions: Our dedicated research labs can simulate a range of storage conditions.
- Microbiological, chemical and physical testing: Log 10 offers the best food microbiology testing lab, running tests to identify a range of microbiological activity.
- Sensory evaluation: Our comprehensive sensory evaluation procedure can meet the needs of any client company and includes trained panelists and customizable attribute testing.
- Technical consultation and research: Log10 offers technical consultation for food safety, guiding and advising you in all your regulatory compliance, food safety training and auditing needs.
Learn more about our range of testing capabilities and food safety services.
Learn More About Our Food Shelf Life Testing Services
Food shelf-life testing is an essential step in the product development process of food manufacturing. If you need quality shelf-life studies, Log10 can assist. Log 10 is a one-stop food safety partner, offering a range of shelf-life testing services as well as analytical food testing services, food safety consulting, training, validation studies and pathogen remediation.
If you want to work with a leader in the food safety industry, choose Log 10.
To learn more about our shelf life testing and other food safety services we provide Contact Log 10 today